Volvo 740 GLE 1986 Temperature Control Lever Stuck

Ferazi · Post by **Ferazi** » 24 Jan 2009, 12:49

The temperature control lever will not move from the left (cold) to right, leaving me with no heat or defroster.
Any advice or suggestions would be appreciated.

rmcmighty · Post by **rmcmighty** » 24 Jan 2009, 14:37

you may have to remove the glove compartment to get at the cable that is attached to the leaver that you are trying to move over to hot !
the cable attaches to another leaver on the heater core and you may be able to move it at that end . Sometimes moisture gets inside and they seize up . you might have to work at it a bit to ease it back and forth and get it free'd up . I used some dry graphite for locks to lube mine up and it works like a champ!
Hope this helps

Kmaniac in California USA · Post by **Kmaniac in California USA** » 24 Jan 2009, 20:55

rmcmighty wrote:you may have to remove the glove compartment to get at the cable that is attached to the leaver that you are trying to move over to hot !
the cable attaches to another leaver on the heater core and you may be able to move it at that end . Sometimes moisture gets inside and they seize up . you might have to work at it a bit to ease it back and forth and get it free'd up . I used some dry graphite for locks to lube mine up and it works like a champ!
Hope this helps

Let me state for the record that there is NO cable running from the temperature slide to the heater core. The temperature slide is a vacuum switch that controls the vacuum operated heater control valve in the engine compartment on one of the heater hoses. This is how it is in my 1986 740 GLE.

You may have to remove the heater control unit in the dashboard to find the root of your problem.

Post by **billofdurham** » 25 Jan 2009, 12:00

There are two types of heater for the '86 740: combu has vacuum operation and without combu has cable operation...... and I don't know what combu stands for!!!!

Bill.

rmcmighty · Post by **rmcmighty** » 25 Jan 2009, 12:24

billofdurham wrote:There are two types of heater for the '86 740: combu has vacuum operation and without combu has cable operation...... and I don't know what combu stands for!!!!

Bill.

Thanks for the save there Bill

rmcmighty · Post by **rmcmighty** » 25 Jan 2009, 12:28

Kmaniac in California USA wrote:
rmcmighty wrote:you may have to remove the glove compartment to get at the cable that is attached to the leaver that you are trying to move over to hot !
the cable attaches to another leaver on the heater core and you may be able to move it at that end . Sometimes moisture gets inside and they seize up . you might have to work at it a bit to ease it back and forth and get it free'd up . I used some dry graphite for locks to lube mine up and it works like a champ!
Hope this helps
Let me state for the record that there is NO cable running from the temperature slide to the heater core. The temperature slide is a vacuum switch that controls the vacuum operated heater control valve in the engine compartment on one of the heater hoses. This is how it is in my 1986 740 GLE.

You may have to remove the heater control unit in the dashboard to find the root of your problem.

My First Volvo Was an 86 740 GLE. When i bought the Car it had been sitting for 2 years. I had the same problem as this Fellow.
I do believe the Combu equipped cars have the automatic climate control feature like my 88 760 it runs completely on vacuum.
I may be Wrong here but. my perception of the whole set up is: if your whole heater control system uses knobs that you turn then your system should run completely on vacuum.
If the heater controls are leavers that you have to slide then the chances of your system using Cables is very good.

Kmaniac in California USA · Post by **Kmaniac in California USA** » 25 Jan 2009, 13:24

Well, I never claimed to be an expert, as my knowledge is limited to what I have in the driveway. So, if I spoke out of turn without all the facts, my apologies. This just goes to show that we all learn something knew everyday.

Ferazi · Post by **Ferazi** » 25 Jan 2009, 14:59

I will assume it's cable to start with. Not today, though, as it's only 12 degrees. This vehicle has also been sitting for almost two years...just too bad it wasn't already set on the warmer end.

Thank you to all who replied. I'll let you know how I get on with it.

Post by **billofdurham** » 25 Jan 2009, 15:25

This just goes to show that we all learn something knew everyday

Chris,

That's what I like about forums and why I devote so much time to them. Until this came up I thought all 700 series heaters had cable controls because mine did. So I have learned something too.

As for "combu" it would certainly seem to be automatic climate control but why don't they just say that?

Bill.

Kmaniac in California USA · Post by **Kmaniac in California USA** » 25 Jan 2009, 15:52

billofdurham wrote:As for "combu" it would certainly seem to be automatic climate control but why don't they just say that?

I DON'T have automatic climate control in my 740, just a heater/air conditioner combination. So maybe there's something more to it.